version bump

Author: dkogan

gnuplotlib.py

@@ -1095,7 +1095,7 @@ class gnuplotlib has a separate gnuplot process and a plot window. If multiple
 gnuplot_executable='gnuplot'
 
 # setup.py assumes the version is a simple string in '' quotes
-__version__ = '0.39'
+__version__ = '0.40'
 
 # In a multiplot, the "process" options apply to the larger plot containing all
 # the subplots, and the "subplot" options apply to each invididual plot.